The disclosure relates generally to performance monitoring, and more specifically to dynamic performance data collection in large computer servers.
An IBM System z® computer is a product line of large computer servers or mainframes based on the z/Architecture® provided by International Business Machines Corporation (IBM®) of Armonk, N.Y. IBM System z® computers can utilize a derivative of the Multiple Virtual Storage (MVS) operating system, which is a robust mainframe operating system utilized by many generations of IBM® mainframe computers. Derivatives of the MVS™ operating system can include the OS/390® operating system and IBM z/OS® (IBM System z®, z/Architecture®, IBM®, OS/390® and IBM z/OS® are registered trademarks of International Business Machines Corporation, located in Armonk, N.Y.).
IBM System z® computers typically run mainframe applications based on the programming languages designed for these environments, such as COBOL, PL/I and Assembler. These mainframe applications typically handle high volumes of data and/or high transaction rates within complex systems and user environments. Therefore, these applications are usually critical to the business in which the IBM System z® computer is installed.
Both execution time and cost are factors that must be considered when running mainframe applications. For example, execution time may be critical with respect to the performance of batch systems and with respect to particular response times required by certain applications (such as web-based or other on-line systems). However, increasing data volumes due to higher business complexity can cause batch process to exceed desired time limits and can increase the response times of critical web-based applications to unacceptable levels. Furthermore, mainframe systems are often associated with high operating costs since many businesses pay for mainframes on a usage basis (for example, license costs are often coupled to the number of MIPS (“Million Instructions Per Second”) in a mainframe installation) and also may pay fixed license costs for mainframe software. Given the increasing pressure to reduce IT spending, these costs have become a major problem to many businesses using mainframe computers.
Given the increasing execution time requirements and cost pressures, businesses are forced to evaluate their current mainframe installations. One option available to such businesses is to upgrade the computer hardware. However, this creates additional fixed costs and is typically only a good choice if money is not a primary decision-driving factor or if the company needs to react immediately. Another option is to optimize and tune the system environment and the applications running in the environment. Utilities have been developed to gather specific performance related data in a mainframe environment, but to date these programs have been largely focused on measuring performance at a mainframe job level. These utilities do not provide a flexible way to capture data at more granular levels, such as, for example, a single line of assembler instruction.